Keratoconus: Understanding the Condition and Its Treatment
03/10/2024
05/06/2024
Surely everyone knows that when we peel and say an onion we immediately start crying, but do you know what is the reason for this watering? When an onion is diced or sliced it releases sulfenic acid and enzymes, which join to produce a gas called propanethial S-oxide. This form of sulfuric acid irritates the nerves around the eyes making them tear as a matter of fact this is a defense mechanism of the onions. Onions grow underground and are frequently under attack from critters who try to eat them, to avoid the attack the onions release this lachrymator compounds.
Here are a few tips to avoid tearing when we chop onions, because these gases are very irritants, they can turn your vision blurry and it can be dangerous if you are at the same time managing a sharp knife.
On the other hand, irritation is also different depending on the type of onion, Spring onions are fresh, not dried, and they're less likely to bring you to tears. The same goes for sweet onion varieties such as Vidalia. Try using spring onions during the spring and summer months, and switch to sweet onions in the fall and winter.
Remember not to touch your eyes when you are saying and chopping onions, clean your hands after you are finished. If your eyes are very irritated, flush them with cold water or use a moisturizing drop to clean and calm your eye, if the irritations persist consult with an eye specialist.
Written by:
Dr. Julia Sempere
Consultant Ophthalmologist